On Fri, Sep 15, 2023 at 2:42 AM Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
>
> On Thu, Sep 14, 2023 at 12:18:05PM +0800, Kai-Heng Feng wrote:
> > System cannot suspend more than 255 times because the driver doesn't
> > have corresponding acpi_disable_gpe() for acpi_enable_gpe(), so the GPE
> > refcount overflows.
>
> How can a user know they are seeing this problem? Is there a public
> bug report for it?
Here's the error when it happens:
[46307.532037] intel_ish_ipc 0000:00:1d.0: enable ose_gpe failed
The ticket was filed privately.
>
> > Since PCI core and ACPI core already handles PCI PME wake and GPE wake
> > when the device has wakeup capability, use device_init_wakeup() to let
> > them do the wakeup setting work.
> >
> > Also add a shutdown callback which uses pci_prepare_to_sleep() to let
> > PCI and ACPI set OOB wakeup for S5.
>
> Is this logically required to be part of this patch, or could it be a
> separate patch?
Because that's what 2e23a70edabe ("HID: intel-ish-hid: ipc: finish
power flow for EHL OOB") intended to do, to enable wakeup from S5.
>
> > Fixes: 2e23a70edabe ("HID: intel-ish-hid: ipc: finish power flow for EHL OOB")
> > Cc: Jian Hui Lee <jianhui.lee@xxxxxxxxxxxxx>
> > Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
> > ---
> > drivers/hid/intel-ish-hid/ipc/pci-ish.c | 59 +++++++------------------
> > 1 file changed, 15 insertions(+), 44 deletions(-)
> >
> > diff --git a/drivers/hid/intel-ish-hid/ipc/pci-ish.c b/drivers/hid/intel-ish-hid/ipc/pci-ish.c
> > index 55cb25038e63..65e7eeb2fa64 100644
> > --- a/drivers/hid/intel-ish-hid/ipc/pci-ish.c
> > +++ b/drivers/hid/intel-ish-hid/ipc/pci-ish.c
> > @@ -119,42 +119,6 @@ static inline bool ish_should_leave_d0i3(struct pci_dev *pdev)
> > return !pm_resume_via_firmware() || pdev->device == CHV_DEVICE_ID;
> > }
> >
> > -static int enable_gpe(struct device *dev)
> > -{
> > -#ifdef CONFIG_ACPI
> > - acpi_status acpi_sts;
> > - struct acpi_device *adev;
> > - struct acpi_device_wakeup *wakeup;
> > -
> > - adev = ACPI_COMPANION(dev);
> > - if (!adev) {
> > - dev_err(dev, "get acpi handle failed\n");
> > - return -ENODEV;
> > - }
> > - wakeup = &adev->wakeup;
> > -
> > - acpi_sts = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
> > - if (ACPI_FAILURE(acpi_sts)) {
> > - dev_err(dev, "enable ose_gpe failed\n");
> > - return -EIO;
> > - }
> > -
> > - return 0;
> > -#else
> > - return -ENODEV;
> > -#endif
> > -}
> > -
> > -static void enable_pme_wake(struct pci_dev *pdev)
> > -{
> > - if ((pci_pme_capable(pdev, PCI_D0) ||
> > - pci_pme_capable(pdev, PCI_D3hot) ||
> > - pci_pme_capable(pdev, PCI_D3cold)) && !enable_gpe(&pdev->dev)) {
> > - pci_pme_active(pdev, true);
> > - dev_dbg(&pdev->dev, "ish ipc driver pme wake enabled\n");
> > - }
> > -}
>
> I LOVE the removal of all this code. Thanks for doing it!
Thanks :)
>
> > /**
> > * ish_probe() - PCI driver probe callback
> > * @pdev: pci device
> > @@ -225,7 +189,7 @@ static int ish_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> >
> > /* Enable PME for EHL */
> > if (pdev->device == EHL_Ax_DEVICE_ID)
> > - enable_pme_wake(pdev);
> > + device_init_wakeup(dev, true);
> >
> > ret = ish_init(ishtp);
> > if (ret)
> > @@ -248,6 +212,19 @@ static void ish_remove(struct pci_dev *pdev)
> > ish_device_disable(ishtp_dev);
> > }
> >
> > +
> > +/**
> > + * ish_shutdown() - PCI driver shutdown callback
> > + * @pdev: pci device
> > + *
> > + * This function sets up wakeup for S5
> > + */
> > +static void ish_shutdown(struct pci_dev *pdev)
> > +{
> > + if (pdev->device == EHL_Ax_DEVICE_ID)
> > + pci_prepare_to_sleep(pdev);
>
> There are only five drivers that use pci_prepare_to_sleep(), so I have
> to ask what is special about this device that makes it necessary here?
The idea is that use pci_enable_wake() and pci_set_power_state() in
pci_prepare_to_sleep() to support S5 wakeup, by replacing the original
enable_pme_wake().
>
> It doesn't seem to match any of the scenarios mentioned in
> Documentation/power/pci.rst for using pci_prepare_to_sleep().
>
> Previously EHL_Ax_DEVICE_ID was used only in ish_probe(),
> ish_resume(), and _dma_no_cache_snooping(). None of those look like
> this, so this *looks* like new functionality that could/should be in a
> separate patch.
Because it's for S5 wakeup, so it's not a new functionality.
Kai-Heng
>
> > +}
> > +
> > static struct device __maybe_unused *ish_resume_device;
> >
> > /* 50ms to get resume response */
> > @@ -370,13 +347,6 @@ static int __maybe_unused ish_resume(struct device *device)
> > struct pci_dev *pdev = to_pci_dev(device);
> > struct ishtp_device *dev = pci_get_drvdata(pdev);
> >
> > - /* add this to finish power flow for EHL */
> > - if (dev->pdev->device == EHL_Ax_DEVICE_ID) {
> > - pci_set_power_state(pdev, PCI_D0);
> > - enable_pme_wake(pdev);
> > - dev_dbg(dev->devc, "set power state to D0 for ehl\n");
> > - }
> > -
> > ish_resume_device = device;
> > dev->resume_flag = 1;
> >
> > @@ -392,6 +362,7 @@ static struct pci_driver ish_driver = {
> > .id_table = ish_pci_tbl,
> > .probe = ish_probe,
> > .remove = ish_remove,
> > + .shutdown = ish_shutdown,
> > .driver.pm = &ish_pm_ops,
> > };
> >
> > --
> > 2.34.1
> >
